This kingfisher is endemic to the islands of Bougainville (in the North Solomons) and Guadalcanal (in the South Solomons). It is endangered with 500-2000 mature individuals left it existence. There are two subspecies, bougainvillei and excelsus. The nominate race, bougainvillei, is endangered. It is considered rare and restricted in both distribution and habitat. The total population is estimated at just 250–1,000 individuals. There are few specimens, with the last taken in 1938, and no records thereafter until 1980s. Calls (believed to be of this species) were heard in 1986 at the edge of lowland swamp-forest near Arawa, and a pair was reportedly watched at a nest-hole in the 1980s. Further corroborative evidence is needed, but the island has been off-limits to ornithologists for many years. The lowlands on Bougainville have been partially logged, and heavy logging is likely to recommence once the island re-opens to commercial exploitation, although the species is thought most likely to inhabit montane forest. As a hole-nesting species, it is potentially threatened by introduced rats and cats. Race excelsus is also endangered. It is considered rare and restricted in both distribution and habitat. The total population is estimated at between 250 and 1,000 mature individuals within an overall range of c. 1,700 km². Only a proportion of this range is expected to be occupied. It is known from one immature male and three female specimens, with the last taken in 1953. There have been no definite records until 1990s. In 1994 and 1997, the species was found to be frequent in montane forest above abandoned Betilonga village, where calls were heard from up to six locations around a camp at 1500 m. The first sound recordings, photographs of a male (and specimen) were obtained on Chupukama ridge in September 2015. No other montane sites have been visited on the island. It occurs at elevations above areas of human activity, although much of its suitable habitat is lost due to natural landslips. As a hole-nesting species, it is potentially threatened by introduced rats and cats.